Control of Pathogenic Bacteria in Foods

ABSTRACT

Methods of making coated pet food kibble and the kibble product by coating kibble with a composition that include at least one of: (i) lecithin and chicken fat; (ii) lecithin, a glycerol monoester of a fatty acid, a sugar monoester of a fatty acid, and chicken fat; (iii) lecithin, N α —(C 8 -C 18 ) acyl arginine alkyl (C 1 -C 8 ) ester, and chicken fat; or (iv) N α —(C 8 -C 18 ) acyl arginine alkyl (C 1 -C 8 ) ester-thymol and chicken fat. When the pet food kibble coated with a composition as described above, exhibits amounts of  Salmonella  sp. that are reduced by about 99%. This reduction is effective for at least 60 days post coating when compared to pet food kibble coated with a composition lacking one of (i)-(iv). The compositions are also used in a method for treating raw beef or poultry prior to grinding where the ground meat exhibits amounts of  Salmonella  sp. that are reduced by about 99%.

PRIORITY

This application is a continuation of U.S. application Ser. No.16/950,443 filed Nov. 17, 2020, which is a continuation of Ser. No.16/818,027 filed Mar. 13, 2020, now U.S. Pat. No. 10,842,175, which is adivisional of U.S. application Ser. No. 16/265,515, filed Feb. 1, 2019,now U.S. Pat. No. 10,624,368, which claims priority to U.S. ProvisionalPat. App. No. 62/625,139, filed on Feb. 1, 2018, all of which areincorporated by reference herein in its entirety.

TECHNICAL FIELD

The purpose of this invention is to present a composition for atreatment system for human foods and pet foods. Compositions can bespecially designed to bring preservatives or other ingredients that haveinhibitory characteristics in contact with bacteria.

BACKGROUND

It is well known that there have been serious bacterial contaminationissues in the recent past in both human food and companion pet food. Itwould be desirable to prevent bacterial contamination in the fattysections of dry pet foods and fatty human food. Salmonella bacteria livein the intestines, both human and animal, and meat may becomecontaminated if animal feces spreads during the butchering process.Seafood, fruits and vegetables can also become tainted by contaminatedwater. It is well known that there have been serious bacterialcontamination issues in the recent past in both human food and companionpet food. However, there are no published methods found to reachcommonly found bacteria, e.g. salmonella, etc. in the fat portions offoods utilizing commonly used preservatives.

One reason is that consumers are aware of non-green and naturaladditives in food, and since the invention of the internet, more peopleare educated about chemicals used to process their foods that might beretained.

In Pohlman, F. et al., Meat Sci. 2002 April; 60(4):349-56, 0.5%cetylpyridinium chloride (CPC) was applied to beef trimmings eitheraerobically or under vacuum before grinding. Beef trimmings wereinoculated with Salmonella typhimurium then treated with CPC in vacuumor aerobic conditions.

In Chen, X. et al., J Food Prot. 2014 November; 77(11):1882-8, groundchicken was reported to likely have higher microbiological loads thanwhole carcasses and parts. Five treatments (0.003% chlorine, 0.07 and0.1% peracetic acid [PAA], and 0.35 and 0.6% cetylpyridinium chloride[CPC]) were evaluated. Results from this study indicated that using PAAas an antimicrobial agent in a postchill decontamination tank to treatground poultry parts is effective for the reduction of Salmonella.

In Sharma, C. et al., the authors report the efficacy of lauric arginate(LAE) on Salmonella survivability in ground chicken containing 9.8% fatwas determined under refrigerated storage and concluded that, althoughLAE possesses strong inhibitory (P<0.05) effect against Salmonella insuspension in 0.1% peptone water, no inhibitory (P>0.05) effect ongrowth of Salmonella was observed in ground chicken at the currentlyapproved levels of 200 ppm.

Kibble and Pet Food

Pet food is a specialty food for domesticated animals that is formulatedaccording to their nutritional needs. Some type of extrusion is commonlyused. It generally consists of meat, meat byproducts, cereals, greens,vitamins, and minerals. Biscuit type pieces are called “kibble”. To meetnutritional requirements, pet food manufacturers blend animal fats, e.g.chicken fat, etc., and meals with soy and wheat grains and vitamins andminerals. This yields a cheap, nutritious pellet that no one wants toeat.

The primary ingredients in pet food are byproducts of meat, poultry, andseafood, food feed grains, and soybean meal. Other ingredients mayinclude salt, preservatives, stabilizers, and chilling agents. Kibblegenerally contains about 10% moisture. The following is the currentgeneral method of manufacturing dry pet food (kibble): dry meal isheated with steam, and moisture is added to approximately 25 wt % level;the wet meal is extruded under pressure and cut to size; the kibble isconveyed with air on to a dryer bed at approximately <220° F.; thekibble are dried down to a moisture level of 6 to 8 wt %; the kibble aresifted to remove broken and fines. Also, the kibble may be sprayedsometimes with another wet coating, usually a liquid flavor (“palatant”)that is water-based. It is during drying and sifting steps thatcontamination where microbes like salmonella strains can be introduced,and this presents a serious problem. Anytime you introducewater/moisture, the probability of introducing pathogens is a concern.The instant invention solves the preservative problem without changingthe process with adverse economic effects. The grains, meat, poultryparts, etc. are heated to 250-260 degrees ° F. This step is designed tokill all the pathogens that likely arise from the poultry scraps thatcan contain salmonella. However, many manufacturers do not have goodtemperature control. Also, cross-contamination can occur once the kibbleis placed into storage bins and dryers. The moisture level out of theextruder can be 20-25 wt %. After the drying step, the moisture levelcan be 8-10 wt %. The extruder is intended to be the kill step, howeverbecause of the moisture level there can be growth from crosscontamination in the manufacturing facility. The normal manufacturingprocedure is to coat the extruded kibble with fat and then a flavorcoating (called a palatant) can be added by spraying. Poultry fat iscommonly used as a coating for kibble.

Shelf life of kibble is usually 1 to 1½ years, however the shelf life ofthe palatant can be much shorter, e.g. possibly three months. If thekibble factory is contaminated with salmonella, the bacteria can fallinto the production lines and get packaged into the kibble bags. Dogsare relatively resistant to salmonella and usually do not show signs ofillness from eating contaminated kibble. But humans who handle the foodor the dog can acquire the bacteria and get sick. This makes dry dogfood a potentially hazardous product, one best kept away from peoplewith weak immune systems such as young children and the elderly.

Present kibble products are commonly preserved with potassium benzoate,sorbate or similar. These are water soluble and do not have the abilityto penetrate fat and reach any bacteria hiding inside.

Human infections of salmonella have been traced back to contaminatedfeed. From the CDC website, “Multistate Outbreak of SalmonellaSchwarzengrund Infections Linked to Dry Pet Food (FINAL UPDATE)” PostedSep. 4, 2007, the CDC is collaborating with public health officials inPennsylvania and other state health departments and the US FDA toinvestigate a multistate outbreak of Salmonella serotype Schwarzengrundinfections in humans.

In. Maciorowski, K. et al., World's Poultry Science Journal, Volume 60,Issue 4, December 2004, pp. 446-457, the authors report thattransmission of food-poisoning salmonellae in the poultry industry isoften associated with a contaminated feed supply.

SUMMARY

This invention discloses the use of emulsifying agents and surfactantswith or without preservatives to penetrate fat in both human and animalfoods and to control the growth of salmonella and other pathogenstherein. These emulsifying agents/surfactants include sucrose monoestersof fatty acids, glycerol monoesters of fatty acids, and lecithin, forexample.

The instant invention demonstrates compositions that can penetrate fatthat is used to coat pet food, e.g. dry kibble, etc., and reach pathogenwithin the coating of a kibble. The instant invention discloses a methodto penetrate the fat coating on kibble to reach the Salmonella that isnot adequately killed in the manufacturing process for kibble.

The compositions of the invention can also penetrate fat of productssuch as ground beef, or ground poultry. The instant invention disclosesthe use of emulsifying agents with or without other preservatives, suchas, benzoates sorbates, nitrates, sulfites, lauric arginate, topenetrate fat in both human and animal foods and to control the growthof salmonella and other pathogens. These emulsifying agents include 1)sucrose monoesters of fatty acids; 2) glycerol monoesters of fattyacids; and 3) lecithin.

The method in the instant invention of treating human food, such asground beef or ground turkey, would entail coating the scraps of beefand turkey prior to a grinding step with the compositions of the instantinvention, similar to how dry kibble is coated. This will assure thatthe distribution of the compositions is evenly distributed in the groundproduct but also be more effective than post adding the compositionsafter the grinding process because of the difficulty of reaching andevenly distributing the composition of the instant invention by postadding into the ground meat product.

DETAILED DESCRIPTION

The inventors have several patents and patent applications that disclosegreen and natural GRAS food preservatives, lauric arginate (LAE), aswell as synergies of LAE with emulsifiers, e.g. glycerol monoesters,including U.S. Pat. Nos. 8,734,879; 9,271,495; 8,834,857, 8,926,997,PCT/US2014/051293, WO 2016/024999 the contents of which are allincorporated by reference in their entirety.

The purpose of this invention is to present a composition for treatmentof foods, e.g. human foods such as ground beef or ground turkey and petfoods such as kibble. The compositions are specially balanced to bringpreservatives or other ingredients that have inhibitory characteristicsin contact with bacteria. This system can be adjusted to maximizeeffectiveness depending on where and on what the preservatives or otheringredients that have inhibitory characteristics are to be used.

For purposes of this invention, it is assumed that ground beef orpoultry for human consumption are usually chilled and have severalmonths shelf life. For dry pet food/kibble, the average shelf life is 1year, and that it takes about 30 to 60 days from the time ofmanufacturing until the pet food reaches the consumer. In order toscreen the final product for contamination, a major pet food testing labspecifies only 0, 20, and 60 day recoveries.

Advantages for dry pet food/kibble include but are not limited to:additives that are nutritious; additives that are GRAS; process costthat are minimized; additives that are inexpensive; additives arecommercially available in large volumes from multiple sources; a processthat is simple and does not require any additional expense of equipment;no need for additional energy costs.

Compositions of this invention comprise 1) one or more antimicrobial orone or more surfactants/emulsifiers with preservative characteristics,2) one or more surfactants with an average HLB between 7 and 12 value toenable the preservative/antimicrobial agent to reach the bacteria on orwithin the food, 3) an aqueous vehicle to deliver the systemingredients, 4) optionally buffers to maintain a pH between about 2.0 to7.0, 5) optionally a chelating agent, and 6) optionallyenhancers/synergists to the preservative system.

As noted above, a particularly serious problem to be dealt with inpreserving foods is due to the penetration of fats and oils withpathogenic bacteria, such as Salmonella. In many cases bacteria trappedin fats and oils cannot be reached using preservatives alone.Furthermore, even if an antimicrobial can reach the target bacteria,kill is not generally achieved in the absence of any water because thebacteria often become dormant and cannot metabolize the antimicrobialmaking it ineffective.

Accordingly, the surfactants in the compositions of this inventionenhance the interaction of the composition with the bacteria by ensuringcontact and by introducing moisture to activate the anti-microbials. Inorder to decontaminate oils and fats on or within foods, this inventionemploys surfactants to emulsify small amounts of aqueous preservativeand moisture into the fats and oils present in the food.

Surfactants optimize the HLB to help the aqueous system containing thepreservative, to either more effectively wet food surfaces or topenetrate into the oils and fats. Wetting of surfaces is best achievedwith surfactants.

Fats and oils in foods can be generally best be emulsified in aqueoussolution using surfactants having an HLB somewhere between about 6 and12. An oil in water emulsion is best formed with an emulsifier of HLBbetween about 12 and 16, while a water in oil emulsion is best formedwith an emulsifier of HLB between about 3 and 7.0.

In addition to HLB, a second factor in choosing an emulsifier is thelength of the hydrophobe chain. In general, longer fatty chains aregenerally more effective in penetrating fats and oils. The hydrophobechain length should be between 12 and about 18 carbons, more preferablybetween about 16 and 18.

Where bacteria are more likely to be located on the outside of foodsurfaces, a wetting agent type of surfactant is preferred for theaqueous preservative system. There are a broad range of surfactants withreasonably good wetting properties, with an HLB, between about 6 andabout 12.

If the surfactants are themselves preservatives, the HLB of the additivesurfactant needs to be adjusted to bring the HLB of the completeantimicrobial system into the preferred HLB range for the application.

Specific embodiments of claims disclose a method to penetrate the fatcoating on kibble to reach Salmonella that is not adequately killed inthe manufacturing process for kibble for up to 60 days.

Even more specifically this invention also discloses that thecompositions of the instant invention can also penetrate fat and kill orinhibit pathogens in other types of fatty foods, such as, ground beef orground poultry, for example.

In yet another embodiment, some compositions of the instant inventionprove to have inhibitor activity on Salmonella in chicken fat using anemulsifier with no reported antimicrobial activity, such as lecithin.

In yet another embodiment, some compositions of the instant invention,such as LAE-thymol, have inhibitory activity on Salmonella without anemulsifier or separate surfactant.

Description of Ingredients

Numerous GRAS (generally regarded as safe or generally recognized assafe) emulsifiers were examined as potential surfactants, penetrators,and/or solubilizers of chicken fat which is commonly used in the pet forindustry to coat kibble, and chicken fat is where pathogen contaminationin the manufacture of pet food/kibble has occurred. The instantinvention has considered and evaluated sugar monoesters, glycerolmonoesters, and lecithin as potential means of allowing preservatives,or other ingredients that have inhibitory characteristics to penetratethe chicken fat and kill pathogens.

It was determined to utilize only GRAS approved ingredients and tominimize the number of processing steps, so that any new innovationswould not be prohibited due to government regulations or due toincreasing the processing costs associated with what the industry ispresently doing.

The first item was to find GRAS approved substances for human andpet/kibble feed that had a preserving ability to inhibit salmonelladosed into chicken fat up to 60 days under normal storage conditions.

The compositions described herein can be referred to a preservatives,antimicrobials, penetrating, emulsifiers, surfactants, co-surfactants,or compositions. Each of the compositions, when added to chicken fatprovides the effect, when coated on a pet food or human food, ofpreventing growth of Salmonella sp over an extended period of time, forexample 60 days. This effect may be termed alternatively, preservationor anti-microbial activity.

The compositions described herein are effective at reducing by about 99%the amount of Salmonella sp. present on kibble or raw meats whencompared to kibble treated with a composition lacking a lecithin; aglycerol monoester of a fatty acid; a sugar monoester of a fatty acid;or a N^(α)—(C₈-C₁₈) acyl arginine alkyl (C₁-C₈) ester salt for anextended period of time. The Examples and methods described herein referto standards used in the industry for testing of food contamination. Forexample, pet food kibble is typically tested for a time period ofbetween 0 and 60 days, and in particular 30 and 60 days. Human foodtesting varies, but can be anywhere from 1 day to 28 days depending uponthe protocol. The extended period of time of the instant invention is aperiod of time greater than one day up to a period of time specified byany available testing protocol. The extended period of time may include1 day, 3 days, 7 days, 28 days, 30 days, 60 days, or 120 days, or anyday in between 1 day and 120 days, for example, 3 days, 30 days, or 60days.

Antimicrobial Salts

The antimicrobial or preservative agent chosen needs to be effectiveagainst a broad range of bacteria such as Salmonella, Listeria, E. coli,S. aureus, Clostridium, Campylobacter, and other pathogens found infood. The agents optionally incorporated into this invention include anyfood-safe, antimicrobial or preservative agent that is effective atcontrolling the target pathogens. Preferred preservatives include thesalts of lauroyl or cocoyl ethyl ester of arginine (LAE or CAE).Preferred salts of LAE and CAE include those that are water-soluble likethe hydrochloride, acetate, lactate, as well as those that can providecontrolled release properties due to their limited aqueous solubility,such as thymol, octanoate, decanoate, laurate, cocoate, myristate,palmitate and stearate or other fatty acid salts. The preferred releasesalts with limited solubility can also help penetration into fats andoils and can prevent loss of activity over time. Other suitablepreservatives include alcohol fatty esters such as glycerolmonooctanoate, glycerol monodecanoate, glycerol monomyristate andglycerol monopalmitate.

In the presence of fat, combining low water soluble salts withcontrolled release properties of LAE or CAE with emulsifying agentsand/or suitable hydrophobic surfactants disclosed in the instantinvention helps to spread into the fat and reach bacteria deep withinthe fat. These surfactants are less likely to help emulsify potassiumbenzoate or sorbate within the fat because of the water solubility andhydrophilic nature of these preservatives. The ingredients in theinstant invention are themselves surfactants and together with the rightsurfactant system will readily spread with the target fats.

Furthermore, other conventional preservatives can be used including inaddition to the compositions described herein and include, but are notlimited to, ascorbic acid, acetic acid, benzoic acid, citric acid,erythorbic acid, lactic acid, sorbic acid, tartaric acid, propionicacid, and their sodium, potassium, ammonium and calcium salts.Additionally, effective preservation can be achieved using solublenitrite, nitrate, sulfite, bisulfite, metabisulfite, dithionite, andbiacetate salts. Additionally methyl, ethyl and propyl andbutyl-p-hydroxy benzoate, methyl, ethyl, propyl and butyl paraben can beused as preservatives.

Lecithin

Lecithin (from the Greek lekithos, “egg yolk”) is a generic term todesignate any group of yellow-brownish fatty substances occurring inanimal and plant tissues, which are amphiphilic—they attract both waterand fatty substances (and so are both hydrophilic and lipophilic), andare used for smoothing food textures, dissolving powders (emulsifying),homogenizing liquid mixtures, and repelling sticking materials.Lecithins are mixtures of glycerophospholipids includingphosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, andphosphatidic acid.

Lecithin has emulsification and lubricant properties, and is asurfactant. It can be totally metabolized (see Inositol) by humans, sois well tolerated by humans and nontoxic when ingested; some otheremulsifiers can only be excreted via the kidneys.

According to ADM (ADM refers to Archer Daniels Midland), the majorcomponents of commercial soybean-derived lecithin are: 33-35% Soybeanoil; 20-21% Inositol phosphatides; 19-21% Phosphatidylcholine; 8-20%Phosphatidylethanolamine; 5-11% Other phosphatides; 5% Freecarbohydrates; 2-5% Sterols; 1% Moisture.

Lecithin is used for applications in human food, animal feed,pharmaceuticals, paints, and other industrial applications. In animalfeed, it enriches fat and protein and improves palletization. Thenontoxicity of lecithin leads to its use with food, as an additive or infood preparation. It is used commercially in foods requiring a naturalemulsifier or lubricant. Lecithin is approved by the United States Foodand Drug Administration for human consumption with the status “generallyrecognized as safe” or “GRAS”. Lecithin is admitted by the EU as a foodadditive, designated as E322. As an emulsifier, soy lecithin is used infood applications as an aerating agent, viscosity modifier, dispersantand lubricant.

Typically, an emulsion is a suspension of small droplets of one liquidin another liquid with which it is incapable of mixing. Oil-in-water(O/W) and water-in-oil (W/O) are the two primary types of emulsions.Lecithin's molecular structure makes it an effective emulsifier for theinteraction of water and oil. Phospholipids, the major component oflecithin, are partly hydrophilic (attracted to water) and partlyhydrophobic (repelled from water). It is lecithin's ability tosimultaneously interact with both oil and water that makes it such aneffective and stable emulsifier. When introduced into a system, anemulsifier such as lecithin acts to help maintain a stable emulsionbetween two unmixable liquids. The emulsifier decreases the surfacetension between the two liquids and allows them to mix and form astable, heterogeneous dispersion.

Hydrophilic-Lipophilic Balance or “HLB” is an index of the predictedpreference of an emulsifier for oil or water—the higher the HLB, themore hydrophilic the molecule; the lower the HLB, the more hydrophobicthe molecule. According to ADM, typical usage levels of lecithin in anemulsion system are: 1-5% of the fat for W/O; 5-10% of the fat for O/W.The amount of lecithin used is dependent upon factors such as the pH,the inclusion of proteins, and the salt concentration.

Sugar Esters

Sugar esters have a wide variety of applications. Mixtures ofregioisomers, as well as mono-, di- and tri-esters are used asemulsifiers, whose resulting physicochemical properties depend on theaverage degree of substitution and fatty acid chain length. They areused as non-ionic surfactants, bleaching boosters and food additives.Sucrose esters of fatty acids with a low degree of substitution can beused as food and cosmetic emulsifiers.

Particular examples of suitable surfactants for use in the providedcompositions include as non-ionic surfactants sugar derived surfactants,particularly fatty acid esters of sugars and sugar derivatives. Forexamples, sugar fatty acid esters include fatty acid esters of sucrose,glucose, maltose and other sugars, esterified to fatty acids of varyinglengths (e.g., varying numbers of carbons). The fatty acids typicallyhave carbon chains between 8 and 28 carbons in length, and typicallybetween 8 and 20, or between 8 and 18 or between 12 and 18, such as, butnot limited to, stearic acid (18 carbons), oleic acid (18:1 carbons),palmitic acid (16 carbons), myristic acid (14 carbons) and lauric acid(12 carbons). Typically, the sugar ester surfactants are sucrose estersurfactants, typically sucrose fatty acid ester surfactants. A preferredsugar fatty acid ester is sugar C8-C18 fatty acid ester.

Sucrose Fatty Acid Ester Surfactants

Sucrose fatty acid ester surfactants contain one or more sucrose fattyacid esters, which are non-ionic surfactants that contain sucrose in thehydrophilic portions and fatty acids in the hydrophobic portions. Thesucrose fatty acid esters can be made by well-known methods (see, forexample, U.S. Pat. Nos. 3,480,616; 3,644,333; 3,714,144; 4,710,567;4,898,935; 4,996,309; 4,995,911; 5,011,922; and 5,017,697 andInternational Patent Application Publication No. WO 2007/082149),typically in an esterification reaction as described below.

Because sucrose contains eight hydroxy (OH) groups, the esterificationreaction can join the sucrose molecule to one fatty acid molecule, orcan join it to a plurality of fatty acid molecules, producing differentdegrees of esterification, e.g., mono-, di-, tri- and poly-(up to octa-)fatty acid esters, but primarily mono-, di-, and/or tri-esters. Therelative amounts of mono- di- tri- and/or poly-esters can depend onreaction conditions.

The fatty acid in the sucrose fatty acid ester can be any fatty acid,and can contain between 4 and 28 carbon atoms, typically between 8 and28 carbon atoms, and typically between 8 and 25 carbon atoms, such asbetween 8 and 18 carbon atoms. The fatty acid can be synthetic ornaturally occurring, and include linear or branched fatty acids. Thefatty acids include, but are not limited to, lauric acid, myristic acid,palmitic acid, stearic acid, oleic acid, caproic acid, capric acid,decanoic acid and pelargonic acid. The more preferred sugar ester ofthis invention is sucrose monolaurate (“SL”). The sugar fatty acidesters used in the data generation for this invention were supplied byMitsubishi Kagaku Foods Corporation. The SL used was Ryoto Sugar EsterL-1695 at 80% monoester. For purposes of this disclosure, “SL types”refers to sucrose fatty acid ester surfactants.

To optimize the overall desired properties, the monoester of sucroseshould be greater than or equal to 70 wt % of total ester content, thehigher the better

Monolaurin

US patents (U.S. Pat. No. 8,193,244B1 and U.S. Pat. No. 9,023,891 B2)disclose the use of monoglycerides consisting of those esters formedfrom saturated fatty acids having from 6 to 14 carbon atoms for theirspermicidal, antimicrobial and cytocidal activity in uses such as foodpreservatives, medical, personal care and hygiene, cosmetics, medical,and related applications. The object of these previous inventions is theprovision of an enhanced combination of N^(α)—(C8 to C16) alkanoyldibasic amino acid (C1 to C12) alkyl ester salts and (C8-C16) fatty acidmonoglycerol esters as the basis for antimicrobial compositions andpreservatives. Specifically, the preferred monoester in the inventors'previous patents is glycerol monolaurate (Monolaurin or “ML”). U.S. Pat.No. 8,193,244B1 and U.S. Pat. No. 9,023,891 B2 are included in thisapplication in their entirety.

There are two factors to consider when choosing the glycerol monoesterof a fatty acid. The ester part could be from C₈-C₁₈ saturatedhydrocarbon, however the C₁₂ has been consistently shown to be theoptimal choice, since when esterifying glycerin it is possible to obtaindi- and tri-esters as well as the monoester. Therefore, in order toachieve the best antibacterial effect, the monoester of monolaurinshould be greater or equal to 70 wt % of the total ester content thehigher being the better.

Therefore the two GRAS approved food additives that were evaluated inthe instant invention, 1) glycerol mono-fatty acid. esters (C₈-C₁₈),e.g. monolaurin (“ML”), and 2) sucrose mono-fatty esters (C₈-C₁₈), e.g.sucrose laurate (“SL”), sucrose myristate, sucrose palmitate, or sucrosestearate, are well described in the literature.

The amount of glycerol mono-fatty acid esters (C₈-C₁₈) can range fromabout 0.01 to about 7.5 wt % added to the kibble. The preferred amountof glycerol mono-fatty acid. esters (C₈-C₁₈) can range from about 0.02to about 5.0 wt % added to the kibble. The most preferred amount ofglycerol mono-fatty acid esters (C₈-C₁₈) can range from 0.04 to about2.5 wt % added to the kibble. The most preferred of the C₈-C₁₈monoesters of glycerol is monolaurin (“ML”). The amount of the C₈-C₁₈monoesters of sucrose can be from about 0.02 to about 15.0 wt % added tothe kibble. The preferred amount of the C₈-C₁₈ monoesters of sucrose canbe from about 0.04 to about 10 wt % added to the kibble. The mostpreferred amount of the C₈-C₁₈ monoesters of sucrose can be from about0.08 to about 7.5 wt % added to the kibble. The most preferred of theC₈-C₁₈ monoesters of sucrose is sucrose laurate. The amount of lecithincan range from about 0.05 to about 30.0 wt %, added to the kibble. Thepreferred amount of lecithin can range from about 0.1 to about 20.0 wt %added to the kibble. The most preferred amount of lecithin can rangefrom about 0.15 to about 15.0 wt %, added to the kibble.

The amount of the N^(α)—(C₈-C₁₈) acyl arginine alkyl (C₁-C₈) ester canrange from about 0.002 to about 4.0 wt % added to the kibble.

The preferred amount of the N^(α)—(C₈-C₁₈) acyl arginine alkyl (C₁-C₈)ester can range from about 0.004 to about 3.0 wt % added to the kibble.The most preferred amount of the N^(α)—(C₈-C₁₈) acyl arginine alkyl(C₁-C₈) ester can range from about 0.008 to about 2 wt % added to thekibble.

The amount of glycerol mono-fatty acid. esters (C₈-C₁₈) can range fromabout 0.02 to about 9 wt % added to the ground beef or poultry. Thepreferred amount of glycerol mono-fatty acid esters (C₈-C₁₈) can rangefrom about 0.04 to about 6 wt % glycerol monoester, added to the groundbeef or poultry. The most preferred amount of glycerol mono-fatty acidesters (C₈-C₁₈), can range from about 0.08 to about 5.0 wt % added tothe ground beef or poultry. The amount of the C₈-C₁₈ monoesters ofsucrose can be from about 0.02 to about 18.0 wt % added to the groundbeef or poultry. The preferred amount of the C₈-C₁₈ monoesters ofsucrose can range from about 0.04 to about 12 wt % added to the groundbeef or poultry. The most preferred amount of the C₈-C₁₈ monoesters ofsucrose can be from about 0.02 to about 7.5 wt % added to the groundbeef or poultry. The most preferred of the C₈-C₁₈ monoesters of sucroseis sucrose laurate. The amount of lecithin can range from about 0.05 toabout 30.0 wt %, added to the added to the ground beef or poultry. Thepreferred amount of lecithin can range from about 0.1 to about 25.0 wt%, added to the ground beef or poultry. The most preferred amount oflecithin can range from about 0.25 to about 20 wt %, added to the groundbeef or poultry. The amount of the N^(α)—(C₈-C₁₈) acyl arginine alkyl(C₁-C₈) ester can range from about 0.002 to about 4.0 wt % added to theground beef or poultry. The preferred amount of the N^(α)—(C₈-C₁₈) acylarginine alkyl (C₁-C₈) ester can range from about 0.004 to about 3.0 wt% added to the ground beef or poultry. The most preferred amount of theN^(α)—(C₈-C₁₈) acyl arginine alkyl (C₁-C₈) ester can range from about0.008 to about 2 wt % added to the ground beef or poultry.

The most preferred N^(α)—(C₈-C₁₈) acyl arginine alkyl (C₁-C₈) ester isLAE-HCl. The most preferred low water soluble salt of N^(α)—(C₈-C₁₈)acyl arginine alkyl (C₁-C₈) ester is LAE-Thymol.

The amount of glycerol mono-fatty acid. esters (C₈-C₁₈), e.g. monolaurin(“ML”), can range from about 0.05 to about 10.0 wt. % added to thechicken fat, i.e. based on 100 g kibble, the level can range from 0.0005to about 0.10 wt. % added to the kibble. The amount of the C₈-C₁₈monoesters of sucrose can be from about 0.1 to about 20.0 wt % added tothe chicken fat added to the chicken fat i.e. based on 100 g kibble, thelevel can range from 0.001 to about 0.20 wt. % added to the kibble.

As can be seen by the Examples, a method of making an improved pet foodkibble comprising is fully described. Methods of making coated pet foodkibble and the kibble itself are fully described. The method includesobtaining pet meal formed into a kibble shape and coating the kibbleshaped pet meal with a composition. The composition may include anycombination of chicken fat with one or more of: a lecithin; a glycerolmonoester of a fatty acid; a sugar monoester of a fatty acid; and aN^(α)—(C₈-C₁₈) acyl arginine alkyl (C₁-C₈) ester salt with the provisothat the combinations each reduce by about 99% for an extended period oftime the amount of Salmonella sp. present on kibble when compared tokibble treated with a composition lacking a lecithin; a glycerolmonoester of a fatty acid; a sugar monoester of a fatty acid; or aN^(α)—(C₈-C₁₈) acyl arginine alkyl (C₁-C₈) ester salt. The compositionmay include at least one of: (i). from about 0.05 to about 30 wt %lecithin and from about 0.5 to about 99 wt % chicken fat; (ii). 0.05 toabout 30 wt % lecithin, from about 0.01 to about 7.5 wt % glycerolmonoester of a fatty acid, from about 0.02 to about 15.0 wt % sugarmonoester of a fatty acid, and from about 0.5 to about 99.0 wt % chickenfat; (iii). 0.05 to about 30.0 wt % lecithin, from about 0.002 to about4.0 wt % N^(α)—(C₈-C₁₈) acyl arginine alkyl (C₁-C₈) ester, and about 0.5to about 99.0 wt % chicken fat; (iv). from about 0.002 to about 4.0 wt %of N^(α)—(C₈-C₁₈) acyl arginine alkyl (C₁-C₈) ester-thymol and 0.5 toabout 99.0 wt % chicken fat. The composition used may also be acombination of any of (i), (ii), (iii), and (iv). When the pet foodkibble coated with a composition as described above, with at least oneof (i)-(iv), the kibble exhibits amounts of Salmonella sp. that arereduced by about 99%. This reduction is effective for at least 60 dayspost coating when compared to pet food kibble coated with a compositionlacking one of (i)-(iv).

The method of obtaining pet meal formed into a kibble shape may include:adding moisture to a dry meal to obtain wet meal; extruding wet mealunder pressure and cutting to preferred kibble size; drying kibble to amoisture level of about 6 to about 8 wt %; sifting to remove broken andfines, so as to result in a kibble-shaped pet meal.

The step of coating the kibble shaped pet meal may include at least onestep of spraying the composition on the kibble or submersion of thekibble in the composition.

Each of compositions (i)-(iv) may further include buffers to maintain pHof less than 7 or a chelant, such as EDTA. Each of preservativecompositions (i)-(iv) may further include a flavoring, coloring orenhancer.

In some cases, the glycerol monoester of composition ii is monolaurinand the sugar monoester of composition ii is sucrose laurate; or theN^(α)—(C₈-C₁₈) acyl arginine alkyl (C₁-C₈) ester of composition (iii) isLAE-HCl.

Also disclosed are methods of treating raw beef or poultry prior togrinding with a composition. The compositions may be one or more of: i:from about 0.05 to about 30.0 wt % lecithin; ii. about 0.05 to about30.0 wt % lecithin, about 0.02 to about 9.0 wt % glycerol monoester, andfrom about 0.02 to about 18.0 wt % sugar monoester of a fatty acid; iii.from about 0.05 to about 30.0 wt % lecithin and from about 0.002 toabout 4 wt % Nα-(C8-C18) acyl arginine alkyl (C1-C8) ester; and iv. fromabout 0.002 to about 4.0 wt % LAE-thymol, and any combination of (i),(ii), (iii), and (iv), all weights based on the total weight of the beefor poultry parts being ground. In use, the beef or poultry is coatedwith a composition having at least one of the compositions (i)-(iv)prior to grinding the beef or poultry. The ground beef or poultryexhibits amounts of Salmonella sp. present in the ground beef or poultryreduced by about 99% for at least 3 days post coating when compared toraw beef or poultry coated with a composition lacking one of (i)-(iv).

Each of compositions (i)-(iv) used to treat raw beef or poultry mayfurther include buffers to maintain pH of less than 7 or a chelant, suchas EDTA. In some cases, the glycerol monoester of composition (ii) ismonolaurin and the sugar monoester of composition (ii) is sucroselaurate; or the N^(α)—(C₈-C₁₈) acyl arginine alkyl (C₁-C₈) ester ofcomposition (iii) is LAE-HCl.

Examples

The following examples are set forth to assist in understanding theinvention and should not, of course, be construed as specificallylimiting the invention described and claimed herein. Such variations ofthe invention, including the substitution of all equivalents now knownor later developed, which would be within the purview of those skilledin the art, and changes in formulation or minor changes in experimentaldesign, are to be considered to fall within the scope of the inventionincorporated herein.

The following abbreviations may be found throughout the Examples. “LAEHCL” refers to N^(α) C₈-C₁₆ alkanoyl-L di-basic amino acid —C₁-C₄ alkylester being N^(α)-lauroyl-L-arginine-ethyl ester HCL salt. “ML” refersto monolaurin. “SL” refers to sucrose laurate. “DW” refers to distilledwater. “CF” refers to chicken fat. ADM refers to Archer Daniels Midland.“Emulsifier” can be used interchangeably with “lecithin” or any of thetradenames: Ultralec® F, Performix™ E, or Yelkin®1018. RT refers to roomtemperature.

Sample Preparation

Control consisting of 50 g of distilled water (DW) while vigorouslystirring and 50 g of chicken fat (“CF”; for example as sold by AFBInternational, 3 Research Park Drive, St. Charles, Mo. 63304).

Sample #1 was prepared by making an emulsion consisting of adding 7 g ofADM Ultralec® F lecithin to 50 g of distilled water (DW), and thenadding 50 g of chicken fat (“CF”) while vigorously stirring. Total 50 gCF+50 g DW+7 g emulsifier=107 g. This emulsion was clear after sevendays at RT.

Sample #2 was prepared by making an emulsion consisting of adding 7 g ofADM Performix™ E lecithin and 1.0 g of sucrose laurate (“SL”) to 50 g ofdistilled water (DW) while vigorously stirring, then 50 g of chicken fat(“CF”) was added to the mix with continued stirring, then 0.5 g ofmonolaurin (“ML”) was added to the emulsion with continued stirring. Forthe sake of this invention, both ML and SL are defined as “actives”. Itcan be appreciated that SL and ML are both surfactants with inhibitorycharacteristics. ML is known to need solubilization in an aqueoussystem, so it was added as a powder after the CF was added to aid in itssolubilization. This emulsion was clear after seven days at RT. In theinstant invention, SL acts as a solubilizer to the ML. Total “actives”in sample #2 are 1.5 g. Sample #2 consists of 50 g CF+50 g DW+7 g ADMPerformix™ E emulsifier+1.5 gm actives=108.5 g; 1.5 g actives/108.5g=0.014 or 1.4 wt % actives; 10 g emulsion coated onto 100 g kibble=>10g×1.4 wt %/100 g kibble=0.14 g total actives/100 g kibble or 1400 ppm ofactives.

Sample #3 was prepared by making an emulsion consisting of 7 g of ADMPerformix™ E lecithin, 50 g of distilled water (DW), 50 g of chicken fat(“CF”), and 0.1 g of LAE-HCl preservative. The LAE-HCl was dissolvedinto the DW, and separately the lecithin was added to the chicken fat,then both were added together by vigorous mixing. Total 50 g CF+50 gDW+7 g emulsifier+0.1 g LAE-HCl=107.1 g. 0.1 g active preservative/107.1g=0.00093 or 0.093 wt % preservative; 10 g emulsion coated onto 100 gkibble=>10 g×0.093 wt % LAE-HCl preservative/100 g kibble=0.093 g totalpreservative/100 g kibble or 93 ppm. This emulsion was clear after sevendays at RT.

Sample #4 was by making an emulsion consisting of 7 g of ADM Yelkin®1018 lecithin added to 50 g of chicken fat (“CF”) by vigorous mixing,then 50 g of distilled water (DW) was added with continued stirring. Noadditional surfactants or preservatives were added.

Sample #5 was prepared w/o lecithin by dissolving LAE-thymol into 50 gof DW with vigorous mixing, and then the DW+LAE-thymol was added to 50 gof chicken fat with vigorous mixing. LAE-thymol is a controlled releasesalt of LAE with low water solubility as compared to LAE-HCl. Total 0.1g preservative+50 g CF+50 g DW=100.1 g; 0.1 g active preservative/100.1g total=˜0.1 wt % actives; 10 g CF/DW coated onto 100 g kibble=>10 g×0.1wt % preservative/100 g kibble=>0.01 g total preservative/100 g kibbleor 100 ppm.

All samples using CF/DW/emulsifier systems were visually stable afterstorage at RT for one week.

Table 1 summarizes the compositions tested. Each sample contained 50 gchicken fat and 50 g DW; 10 g of each sample was applied to 100 gkibble. Testing and storage was at RT. Samples of coated kibble werekept in sealed plastic bags after applying to the kibble.

TABLE 1 Summary of compositions formulation according to the instantinvention Sucrose LAE- LAE- Lecithin Emulsifier, Chicken DW, Monolaurinlaurate HCl, thymol, Sample Emulsifier g fat, g g (ML) (SL), g g gControl — — 50 50 #1 Ultralec ® 7 50 50 #2 Performix ™ E 7 50 50 0.5 1#3 Performix ™ E 7 50 50 0.1 #4 Yelkin ® 1018 7 50 50 #5 — — 50 50 0.1

Experimental Methods

10 g of each sample and control was applied to 100 g kibble. To applyeach sample to the kibble, all samples were separately shaken onto acommercial kibble using a common hand held “cocktail” shaker. If asample was made with a surfactant/emulsifier, to check the condition ofthe emulsions, each sample was stored in a glass bottle. In a commercialsetting this step can be done either with a revolving pan or with aspray nozzle. There is no anticipated extra step in the overall processas compared with the steps commonly used in the pet food industry tomanufacture kibble. Also the inclusion of the lecithin emulsifier onlyincreases the overall water content by 4 to 8% and it does notnecessitate an extra step to remove this water.

Testing and storage was at RT. Samples of coated kibble were kept insealed plastic bags after applying to the kibble. A sample was removedat 30 days for testing and a sample was removed at 60 days for testing.The kibble samples were challenged with a known load and reduction ofbacteria measured.

Performance kill tests on kibble against a mix of Salmonella bacterialstrains (ATCC 10708, 6539, and 14028), defined in the instant inventionas Salmonella sp., were conducted at 30 and 60 days. At each time point,cfu (colony forming units) were observed. The cfu was converted to a lognumber and the log reduction in colony forming units observed. Thiscalculation is also shown as a percentage.

Results

Table 2 demonstrates the log reduction found at 30 days post coating ofkibble for all five samples.

TABLE 2 colony forming units of Salmonella sp. found on coated kibbleafter 30 days cfu Log % Sample recovered Log reduction reduction Control1.8 × 10⁴ 4.25 0 0 #1 8.5 × 10² 2.9 1.35 92.0 #2 1.0 × 10² 2.0 2.25 99.4#3 2.8 × 10² 2.45 1.80 97.0 #4 4.0 × 10² 2.55 1.70 96.0 6.0 × 10² 2.751.50 94.0

Table 3 demonstrates the log reduction found at 60 days post coating ofkibble for all five samples.

TABLE 3 colony forming units of Salmonella sp. found on coated kibbleafter 30 days Sample cfu recovered Log Log reduction % reduction Control1.8 × 10⁴ 4.25 0 0 #1 2.3 × 10⁴ 4.45 0 0 #2 1.0 × 10¹ 1.05 3.4 99.95 #33.1 × 10³ 3.55 0.9 89.00 #4 2.0 × 10¹ 1.35 3.1 99.92 #5 1.6 × 10² 2.252.2 99.35

Mono fatty acid glycerides, with C6-C18 carbon chain length of the fattyacid, in combination with mono fatty acid sucrose derivatives, fromC6-C18 carbon chain length and suitable emulsifiers, provided theoverall anti-microbial/preservative activity in pet food againstsalmonella contained in chicken fat coated onto kibble. The logreduction was significant for several of the samples tested usingvarious food preservatives (samples #2-5), with some compositions of theinstant invention without containing lecithin giving significant logreductions (sample #5). Samples also containing only lecithin also gavesignificant log reductions (sample #4). It is very advantageous that allingredients are GRAS approved for food, and they all have nutritionalvalue as food additives. It is expected that there will be no apparenttaste problems at the inventive usage levels.

Samples 1-5 showed log reductions after 30 days. Sample 1 showed no logreduction after 60 days, using only an emulsifier with an HLB of 7.(There was also visual growth noted after 60 days). Sample #4 using onlyan emulsifier with an HLB of 11 gave increased log reduction after 60days. Sample #2 with an emulsifier with an HLB of 12 and two GRASsurfactants with inhibitory characteristics gave a increased logreduction after 60 days, while sample #3 with the same emulsifier assample #2 but with a food preservative gave reduced log reduction after60 days. Sample #5 with no emulsifier and no surfactants but with thesalt LAE-thymol, gave an increased log reduction after 60 days. Therewas no mold evident in Sample #3 of coated kibble in a sealed plasticbag using a combination of sucrose laurate and monolaurin emulsifiedwith lecithin after 120 days.

Another test using the composition in Sample #3 on poultry utilizing0.093 wt % LAE-HCl (per weight of raw poultry). At 3 day recovery, thecfu 1.51×10⁵, the log 5.18, the log reduction 2, for a % reduction of99.95%. (The control: cfu at 2×10⁷, log 7.3). For Sample #3 coated ontokibble, the log reduction was 1.9 after 30 days and 0.9 after 60 days. Azone of inhibition was done at 1 hour to confirm if these samples hadany preservative activity. A zone of inhibition is used as a screeningtest to determine if further testing should be done for a quantitative,determination e.g. a time kill log reduction. The zone data supports the3 day results that sample 3 is effective at killing salmonella inchicken fat.

As stated above, while the present application has been illustrated bythe description of embodiments thereof and while the embodiments havebeen described in considerable detail, it is not the intention of theapplicants to restrict or in any way limit the scope of the appendedclaims to such detail. Additional advantages and modifications willreadily appear to those skilled in the art, having the benefit of thepresent application. Therefore, the application, in its broader aspects,is not limited to the specific details of the illustrative examplesshown. Departures may be made from such details and examples withoutdeparting from the spirit or scope of the general inventive concept.

1-55. (canceled)
 56. A preservative composition comprising: an effectiveamount of between about 0.002 to about 4.0 wt % of Nα-(C8-C18) acylarginine alkyl (C1-C8) ester-thymol, wherein application of thecomposition is effective for reducing colony forming units of pathogensby about 94% compared to application of a composition lackingNα-(C8-C18) acyl arginine alkyl (C1-C8) ester-thymol.
 57. Thecomposition of claim 56, further comprising a chelating agent EDTA. 58.The composition of claim 56, further comprising buffers to maintain pHof less than
 7. 59. The composition of claim 56, further comprising aflavoring or coloring.
 60. The composition of claim 56, furthercomprising a surfactant.